WASHINGTON - The House Budget Committee voted narrowly Thursday to advance the troubled Republican health care bill, with defections by three GOP conservatives underscoring the obstacles party leaders face in maneuvering to avoid a stinging setback to their showpiece legislation.

The vote was 19-17, with Democrats unanimously voting no. Had one more Republican joined them, the measure would have failed in what would have been a damaging, embarrassing - but not fatal - blow to the measure, despite its backing by President Donald Trump.

The committee planned to debate a slew of non-binding proposals suggesting changes in the measure, with some expected from Republicans. Those may provide clues about the types of changes GOP leaders believe the legislation will need for it to win House approval, which top Republicans hope will occur next week.

Before the vote, panel Chairwoman Diane Black, R-Tenn., appealed to fellow Republicans to back the legislation, calling it "the conservative health care vision we've been talking about for years." The measure would strike down much of former President Barack Obama's 2010 overhaul and reduce the federal role, including financing, for health care consumers.

"Don't cut off discussion. Stay with this effort," she said., calling the measure "a good first step."

Three members of the hard-line conservative House Freedom Caucus - Reps. Dave Brat of Virginia, Gary Palmer of Alabama and Mark Sanford of South Carolina - opposed the measure.

Democrats said the legislation would strip coverage from millions who gained it under Obama's 2010 overhaul and would bestow a massive gift on the wealthy by repealing many of that law's tax increases.

"This is Robin Hood in reverse, but far worse," said the panel's top Democrat, Rep. John Yarmuth of Kentucky. Citing lawmakers' town hall meetings that have been jammed with activists opposing the GOP bill, he said, "This bill is not what the American people want."

The White House and Republican leaders are already talking to rank-and-file Republicans about revising the bill to nail down support.

The committee vote came four days after the nonpartisan Congressional Budget Office projected the legislation would boot 24 million people from health coverage. That includes 14 million who'd lost it next year - a scary scenario for lawmakers facing re-election next year, and overt GOP opposition has grown since that report was released.

The bill would eliminate the tax penalty that pressures people to buy coverage and the federal subsidies that let millions afford it, replacing them with tax credits that are bigger for older people. It would cut Medicaid, repeal the law's tax increases on higher earning Americans and require 30 percent higher premiums for consumers who let coverage lapse.

House Speaker Paul Ryan, R-Wis., told reporters Wednesday that leaders could now make "some necessary improvements and refinements" to the legislation.

At a late rally in Nashville Wednesday, Trump said: "We're going to arbitrate, we're all going to get together, we're going to get something done."

Vice President Mike Pence met with House GOP lawmakers and pressed them to unite behind the legislation.

"‘It's our job to get it out of here and get it to the Senate,'" Pence told Republicans, according to Rep. Dennis Ross, R-Fla. That would let Trump pressure "Democrats in these red states to come on board,'" Ross said, referring to Republican-leaning states where Democratic senators face re-election next year.

But insurgents still abound.

Conservatives want to end Obama's expansion of Medicaid to 11 million additional low-income people next year, not 2020 as the bill proposes. They say a GOP proposed tax credit to help people pay medical costs is too generous, and they want to terminate all of Obama's insurance requirements, including mandatory coverage of specified services like drug counseling.

Rep. Mark Meadows, R-N.C., head of the hard-line conservative House Freedom Caucus, continued pushing for changes. He claimed at least 21 members of his group would oppose the measure as written; the bill would fail if 22 Republicans join all Democrats in opposing it.

But underscoring the push-pull problem GOP leaders face in winning votes, moderates feel the tax credits are too stingy, especially for low earners and older people. They oppose accelerating the phase-out of the Medicaid expansion and are unhappy with long-term cuts the measure would inflict on the entire program.

Terminating the Medicaid expansion in 2020 and not 2018 "is sacrosanct to me," said moderate Rep. Tom MacArthur, R-N.J.

In a new complication, Sen. Charles Grassley, R-Iowa, said the measure lacked the votes to pass in the Senate, where Republicans hold a precarious 52-48 majority. That left House members angry over being asked to take a politically risky vote for legislation likely to be altered.

Moderates "don't like the idea of taking a vote in the House that may go nowhere in the Senate," said Rep. Charlie Dent, R-Pa.